Rotary cassette system for dry powder inhaler

ABSTRACT

The present disclosure provides an inhaler having a vibration element for aerosolizing medicament contained in a blister pack, wherein a plurality of individual blister packs are arranged in a rotary cassette that fits within a housing, and wherein the individual blister packs are dragged up into a clamping position between the vibration element and a piercing element. The motion of the blister pack is controlled by a rotary disk within the housing which further coordinates the movement of the piercing and vibrating elements for the piercing and deaggregation, respectively, of the individual blister packs.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority from the U.S. Provisional ApplicationSer. No. 61/180,396, the contents of which are incorporated herein intheir entirety, by reference.

FIELD OF THE INVENTION

The present disclosure relates generally to the field of inhalationdevices. The disclosure has particular utility in connection with thedelivery of powdered medications to a patient, and will be described inconnection with such utility, although other utilities are contemplated.

BACKGROUND OF THE INVENTION

Certain diseases of the respiratory tract are known to respond totreatment by the direct application of therapeutic agents. As theseagents are most readily available in dry powdered form, theirapplication is most conveniently accomplished by inhaling the powderedmaterial through the nose or mouth. This powdered form results in thebetter utilization of the medicament in that the drug is depositedexactly at the site desired and where its action may be required; hence,very minute doses of the drug are often equally as efficacious as largerdoses administered by other means, with a consequent marked reduction inthe incidence of undesired side effects and medicament cost.Alternatively, the drug in this form may be used for treatment ofdiseases other than those of the respiratory system. When the drug isdeposited on the very large surface areas of the lungs, it may be veryrapidly absorbed into the blood stream; hence, this method ofapplication may take the place of administration by injection, tablet,or other conventional means.

It is the opinion of the pharmaceutical industry that thebioavailability of the drug is optimum when the drug particles deliveredto the respiratory tract are between 1 to 5 microns in size. When thedrug particles need to be in this size range the dry powder deliverysystem needs to address a number of issues:

(1) Small size particles may develop an electrostatic charge onthemselves during manufacturing and storage. This may cause theparticles to agglomerate or aggregate, resulting in clusters ofparticles which have an effective size greater than 5 microns. Theprobability of these large clusters making it to the deep lungs thendecreases. This in turn results in a lower percentage of the packageddrug being available to the patient for absorption.

(2) The amount of active drug that needs to be delivered to the patientmay be of the order of 10s of micrograms. For example, in the case ofalbuterol, a drug used in asthma, this is usually 25 to 50 micrograms.Current manufacturing equipment can effectively deliver aliquots ofdrugs in milligram dose range with acceptable accuracy. So the standardpractice is to mix the active drug with a filler or bulking agent suchas lactose. This additive also makes the drug “easy to flow”. Thisfiller is also called a carrier since the drug particles also stick tothese particles through electrostatic or chemical bonds. These carrierparticles are very much larger than the drug particles in size. Theability of the dry powder inhaler to separate drug from the carrier isan important performance parameter in the effectiveness of the design.

(3) Active drug particles with sizes greater than 5 microns will bedeposited either in the mouth or throat. This introduces another levelof uncertainty since the bioavailability and absorption of the drug inthese locations is different from the lungs. Dry powder inhalers need tominimize the drug deposited in these locations to reduce the uncertaintyassociated with the bioavailability of the drug.

Prior art dry powder inhalers (DPIs) usually have a means forintroducing the drug (active drug plus carrier) into a high velocity airstream. The high velocity air stream is used as the primary mechanismfor breaking up the cluster of micronized particles or separating thedrug particles from the carrier. Several inhalation devices useful fordispensing this powder form of medicament are known in the prior art.For example, in U.S. Pat. Nos. 3,507,277; 3,518,992; 3,635,219;3,795,244; and 3,807,400, inhalation devices are disclosed having meansfor piercing of a capsule containing a powdered medicament, which uponinhalation is drawn out of the pierced capsule and into the user'smouth. Several of these patents disclose propeller means, which uponinhalation aid in dispensing the powder out of the capsule, so that itis not necessary to rely solely on the inhaled air to suction powderfrom the capsule. For example, in U.S. Pat. No. 2,517,482, a device isdisclosed having a powder containing capsule placed in a lower chamberbefore inhalation, where it is pierced by manual depression of apiercing pin by the user. After piercing, inhalation is begun and thecapsule is drawn into an upper chamber of the device where it movesabout in all directions to cause a dispensing of powder through thepierced holes and into the inhaled air stream. U.S. Pat. No. 3,831,606discloses an inhalation device having multiple piercing pins, propellermeans, and a self-contained power source for operating the propellermeans via external manual manipulation, so that upon inhalation thepropeller means aids in dispensing the powder into the stream of inhaledair. See also U.S. Pat. Nos. 3,948,264 and 5,458,135.

In prior U.S. Pat. Nos. 7,318,434 and 7,334,577 incorporated herein byreference, and assigned to the common assignee MicroDose Technologies,Inc., there is provided an improvement over prior art inhalers thatutilize vibration to facilitate suspension of power into an inhaled gasstream and which utilizes synthetic jetting to aerosolize drug powderfrom a blister pack or the like. As taught in the aforesaid U.S. Pat.Nos. 7,318,434 and 7,334,577 there is provided a dry powder inhalerhaving a first chamber such as a blister pack or other container, forand holding a dry powder, and a second chamber connected to the firstchamber via a passageway for receiving an aerosolized form of the drypowder from the first chamber and for delivering the aerosolized drypowder to a user. A vibrator is coupled to the dry powder in the firstchamber. The vibrator is energized and coupled to the first chamber anddrives the powder from the chamber by synthetic jetting.

As described in U.S. Pat. No. 7,080,644 also incorporated herein byreference, and also assigned to common assignee MicroDose Technologies,Inc., controlled aliquots or doses of a medication or drug arepre-packaged in a blister pack, which includes a frangible crowned topelement which may be conical, conical with a rounded point, rounded, orother raised shape configuration, and a bottom element which may be aflat web or membrane, or which itself may be of shaped configuration,e.g. conical, round, dish shaped, etc. for closely engaging with anunderlying vibrating element, the shape and size of which is chosen toprovide optimum controlled delivery of a given medication or drug. Thetop element of the blister pack is pierced with a piercing device suchas a sharp needle to form one or more apertures for delivery of themedication or drug contained within the blister pack. The hole patternand hole size is selected to provide optimization of delivery of theparticular medication or drug packaged therein.

SUMMARY OF THE INVENTION

The present disclosure provides an improvement over the prior artdevices such as discussed above by providing an inhaler having avibration element for aerosolizing medicament contained in a blisterpack, wherein the inhaler is adapted to hold a plurality of individualblister packs which can be individually accessed and moved into anoperative or dispensing position between the vibration element and apiercing element. The advantages of this construction include: simpler,more compact assembly for an inhaler containing a plurality of blisterpacks; and the ability to isolate and shield individual blister packsfrom the piercing element prior to use.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features and advantages of the present disclosure will be seenfrom the following detailed description, taken in conjunction with theaccompanying drawings, wherein

FIGS. 1A and 1B are top views of an inhaler according to the presentdisclosure, displaying different positions of the lever arm;

FIGS. 2A, 2B, and 2C are sectioned views of an inhaler with a rotarycassette activated by a lever arm in accordance with the presentdisclosure;

FIG. 3 is an exploded view of a cartridge assembly in accordance withthe present disclosure;

FIG. 4 is an illustration of a cartridge assembly being loaded into thehousing of an inhaler of the present disclosure;

FIG. 5 is an illustration showing the bottom of an inhaler in accordancewith the present disclosure;

FIG. 6A is an illustration of a blister pack in accordance with thepresent disclosure;

FIG. 6B is an illustration showing the operation of a blister packcarrier in accordance with the present disclosure;

FIG. 7 is a partial view of the internal elements of the dry powderinhaler of the present disclosure;

FIGS. 8 a and 8 b are detailed sectional views of the blister packcarrier and piercing mechanism in accordance with the presentdisclosure;

FIGS. 9A and 9B are detailed section views of the flow channel and thevibrating and piercing elements of the present disclosure;

FIG. 10 is a block diagram showing the operation of the electronicsassociated with the dry powder inhaler of the present disclosure;

FIG. 11 is an illustration of a printed circuit carrier in accordancewith the present disclosure;

FIG. 12 is a sectioned side view of a dry powder inhaler in accordancewith the present disclosure; and

FIG. 13 is an exploded view of a dry powder inhaler in accordance withthe present disclosure.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

In the following description, reference is made to the accompanyingdrawings, which form a part hereof, and in which is shown, by way ofillustration, various embodiments of the present disclosure. It isunderstood that other embodiments may be utilized and changes may bemade without departing from the scope of the present disclosure.

The present disclosure provides a device for delivering medicament tothe airway of a user, wherein the device generally comprises a housingwith a mouthpiece affixed and a cover for the mouthpiece. The housing isadapted to hold a plurality of individual blister packs containing, forexample, powdered medicament. However, the medication could be a liquidform medication. The blisters are arranged such that individual blistersmay be loaded into a clamping position, whereupon the blister is piercedand a vibrating device is used to aggregate the contents of the blister,which is subsequently inhaled by the user. Preferably the blisters arecarried in a cartridge which in a preferred form comprises a rotarycassette containing a plurality of individually addressable blisterpacks. The device also includes a mechanism for moving selected blisterpacks between a stowed position and an operative position. The mechanismmay also be used to activate the piercing and vibrating elements.

Referring to FIGS. 1A and 1B, the inhaler of the present disclosurecomprises a housing 1 having a mouthpiece 2, and a retractable cover 3.The device may also include a lever arm 11, the movement of which opensthe retractable cover and activates other elements of the device, aswill be described in detail below. The retractable cover may also beopened manually, such as when the user desires to clean the mouthpiece,but may not be closed when the lever arm 11 has been moved to an openposition.

Referring to FIGS. 2A-2C, the lever arm 11 is connected to a cam disk 10contained within the housing which translates the rotational motion ofthe lever arm to translational or rotational motion of other internalelements of the device. The device as shown is configured to allow thelever arm to turn 120°, which is a convention range of motion foroperating the device with one hand, but other ranges are also possible.As the lever arm progresses from one position to another (see FIGS.2A-2C), cam disk 10 is turned and retractable cover 3 uncovers themouthpiece 2. The rotation of the cam disk is shown by reference line110.

The distal end of the lever arm (relative to the cam disk) forms abutton area 11A that is configured to allow a user to easily grip andmove the lever arm. For example, the surface area of the button shouldbe large enough to allow easy pulling of the lever arm and the surfaceof the button may also be comprised of a material that enhances the gripof the user. At either end of the motion of the lever arm, the devicemay include a sequence lock that allows the lever arm and cam disk toremain in a fixed position until the user moves the lever arm again.

Alternatively, other motions may be used to activate the device. Forexample, the cover of the device may be connected to the cam disk by alinkage that turns the cam disk when the cover is opened.

Referring to FIGS. 1A and 1B and 2A-2C, the device also includes anindicator 70 that communicates information to the user that may include,for example, a reminder when a new dose is to be administered, anindication of when the user should inhale, an indication of when theuser should be done inhaling, and a warning, for example, when thedevice is empty, the medication is out of date, or the device wassubject to environmental extremes, e.g. heating or cooling, beyond itsdesign range. The device should indicate the inhale signal to the userwhen a blister pack has been opened and can no longer be stored. Aratcheting feature may also be incorporated into the cam disk I 0 toprevent partial or accidental activation of the device.

FIG. 3 shows the different pieces of the cartridge assembly of thepresent disclosure. The cartridge 20 containing the rotary cassette isgenerally arranged such that the plurality of individual blister packs21 are fanned out in a radial pattern relative to the plane of therotary cassette. FIG. 3 shows one cartridge comprising an upper housing23 and a lower housing 24. The cartridge contains a blister carousel 22that separates each of the blister packs 21. The cartridge also includesa blister carrier 27 that is used to move one blister pack at a timealong a radial path into an operating position. The cartridge can beconfigured to carry a wide range of number of blister packs.

As shown in FIG. 4, the cartridge may be removed and reloaded orreplaced so that the device may continue to be used. FIG. 5 shows thatthe cartridge may also include a dose counter 25 for tracking the numberof doses, and a release tab 26 to facilitate removal of the cartridge.

FIG. 6A shows a typical blister pack. Other blister pack designs arealso possible. For examples of other blister pack designs that may becompatible with the device of the present disclosure, see, for example,U.S. Published Application Nos. 2006/0174869 A1, 2008/0202514A1, and2009/0314288 A1. all assigned to a common assignee and incorporated byreference herein. Alternatively, the blister packs may comprise adivided package or blister pack containing two or more medicaments ordrugs, e.g. of the same or different particle size, for co-delivery to auser as disclosed, e.g. in U.S. Published Application No. 2005/0147566A1, also assigned to a common assignee.

As described above, the medicament or drug contained in the blister packis delivered to the patient by pushing a fresh blister pack 21 intoposition using blister carrier 27. The motion of the blister carrier isin a radial direction, as indicated by the arrows in FIG. 6B.

Motion of the blister carrier, as well as the retractable cover isinitiated by the movement of the lever arm 11, the rotational motion ofwhich is transferred to other respective elements using cam disk 10,which includes a series of slots, cams, and/or pins that control themovement of linkages connected to other elements of the device. Theseconnections are demonstrated by FIG. 7, which shows the disposition ofthe various linkages in connection with the cartridge assembly 20, thevibrator assembly 40, and the piercing assembly 50. (The cam disk is notshown in this view). The cam disk connects to a cartridge index linkage13 that turns the cartridge making the next blister pack available aftereach time the device is used; a blister transport linkage 18 that isconnected to blister transport sled 28, which in turn is connected toblister carrier 27; and a vibrator linkage 14; a piercing linkage 15.The cartridge assembly further includes ratchet teeth 12 that enable theindexing feature. The linkages as shown here are merely exemplary.Several other configurations are also possible. For instance, the lengthand number of linkages may be changed while still achieving a similarresult.

Where cams, slots and follower pins, rotating pins, or other piecesconflict with one another, the cam disk 10 may comprise of two flatinner and outer disks joined together, such as for example, being joinedat a hub. In this manner, the disk may include overlapping slots orcams.

Referring to FIGS. 8A, 8B, 9A, and 9B, the blister carrier 27 moves aselected blister pack 21 into position between the piercing assembly 50and the vibrating assembly 40. The top of the blister extends throughopening 31 into flow channel 30, which is connected to mouthpiece 2. Theblister pack is clamped in place by the vibrator assembly 40 whichincludes spring 42 for placing piezoelectric transducer 41 againstblister pack and holding the blister pack in place. Posts 45 may beprovided to ensure that proper contact between the vibrating element andthe blister pack is maintained. Alternatively, the opening 31 in theflow channel 30 may be made large enough to allow the blister pack toextend further into the flow channel, wherein flange area of blisterpack 21 is clamped between the piezoelectric transducer and the flowchannel. Slot 43 is aligned with protrusion 44, limiting the range ofmotion of the spring 42.

The piercing assembly is aligned with the blister pack on the oppositeside of the flow channel with the piercer 51 extending through holes 32when used to puncture the blister pack. The piercer may comprise aneedle or plurality of needles to adequately puncture the blister pack.

The vibrating assembly 40 may include a piezoelectric transducer 41 as avibrating element, but other vibrating elements are also within thescope of the present disclosure, such for example as a microphoneproviding a sonic vibration. The vibrating element causes the powderedmedicament within the blister pack to be aerosolized in the surroundingair and may create a synthetic jet that distributes the medicament intothe flow channel 30. The medicament is then transported into thepatient's inhalation air stream drawn through the mouthpiece 2.

The vibrating element may be activated by flow sensor 60 which sensesthe breath of the patient as described in U.S. Pat. No. 6,152,130 and inco-pending U.S. application Ser. No. 11/064, 201, both of which arecommonly owned and are incorporated herein by reference. Referring toFIGS. 10-12, flow element 60 is comprised of flow sensor 61, the signalof which is conditioned 201 and send to a microprocessor 203. Thecontrol logic within the microprocessor, in connection with the systemclock circuit 202, controls the vibrating element such as piezoelectrictransducer 41 through driver circuit 206. Power to the vibrating elementis supplied by battery 81 which is adjusted by circuit 205. Themicroprocessor also sends a signal to LEDs 71 of user interface 70 wheninhalation is complete. As mentioned above, the microprocessor may alsosend a signal to user interface 70 when a prescribed time has passedsince the previous dose.

Once a blister pack has been emptied, it may be disposed of byextracting the empty blister through the top of the housing next to themouthpiece 2. Alternatively, it may be stored in the cartridge orotherwise out of the way until all the blister packs are depleted, atwhich time a fresh cassette may be loaded into the inhaler after theemptied cassette is removed.

FIG. 13 shows the elements of the present invention in an exploded view.The housing 1 may be comprised of multiple pieces, including devicecover 4 and chassis 5. the printed circuit board assembly 82, whichincludes the microprocessor and various circuits, is connected to theflow sensor by flex wire 62. The assembly shown in FIG. 13 may bemodified without departing from the principles of the presentdisclosure. For example, the cam disk may be reduced in size and take aform other than that of a flat disk, and still provide the samefunction.

It should be emphasized that the above-described embodiments of thepresent device and process, particularly, and “preferred” embodiments,are merely possible examples of implementations and merely set forth fora clear understanding of the principles of the disclosure. Manydifferent embodiments of the rotary cassette system for a dry powderinhaler described herein may be designed and/or fabricated withoutdeparting from the spirit and scope of the disclosure. For example, theeffective delivery of the medicament may be optimized by manipulatingthe waveform of the piezoelectric vibrator. All these and other suchmodifications and variations are intended to be included herein withinthe scope of this disclosure and protected by the following claims.Therefore the scope of the disclosure is not intended to be limitedexcept as indicated in the appended claims.

1. A medication inhaler, comprising a housing; a mouthpiece affixed tothe housing; a vibrating element and a piercing element contained withinthe housing; a plurality of individually addressable blister packscarried within the housing, wherein each of the plurality ofindividually addressable blister packs contains a specified amount of amedicament; and a mechanism that moves selected blister packs between astowed position and a dispensing position.
 2. The inhaler of claim 1,wherein the plurality of blister packs are carried on a cassette.
 3. Theinhaler of claim 2, wherein the cassette is rotatably mounted within thehousing.
 4. The inhaler of claim 1, further comprising a rotatablymounted disk that coordinates movement of one of said plurality ofindividual blister packs into the dispensing position where theindividual blister pack is clamped in between the vibrating element andthe piercing element.
 5. The inhaler of claim 4, wherein the rotary diskfurther coordinates the movement of the piercing element, whereby thepiercing element pierces the blister pack in the dispensing position. 6.The inhaler of claim 4, wherein the rotary disk further coordinatesmovement of the vibrating element whereupon the vibrating element comesinto contact with the blister pack in the dispensing position.
 7. Theinhaler of claim 4, wherein the rotation of the disk is controlled bythe user by using a lever arm that protrudes from the housing.
 8. Theinhaler of claim 4, further comprising a cover for covering themouthpiece pivotally connected to the housing.
 9. The inhaler of claim8, further comprising a linkage connecting the cover with the rotarydisk, wherein the pivotal movement of the disk turns the retracts thecover.
 10. The inhaler of claim 1, wherein the vibrating element is apiezoelectric transducer.
 11. The inhaler of claim 1, further comprisinga battery and a printed circuit board.
 12. The inhaler of claim 1,wherein the plurality of individual blister packs are arranged in acircular plan, and wherein a plane of the blister pack is substantiallyperpendicular to a plane of the cartridge.
 13. The inhaler of claim 4,wherein the disk further coordinates the movement of the rotatablymounted cassette.
 14. The inhaler of claim 1, wherein the medicationcomprises a dry powder.
 15. The inhaler of claim 1, wherein themedication comprises a liquid.
 16. A dry powder inhaler, comprising avibrating element; a piercing element; a cartridge attached containing aplurality of individually addressable blister packs, wherein each of theplurality of individually addressable blister packs contains a specifiedamount of powdered medicament, the blister packs being arranged in acircular formation: and a lever arm, the movement of which causes aselected blister pack to be dragged between the vibrating element andthe piercing element to be deaggregated and inhaled by a user.
 17. Thedry powder inhaler of claim 16, further comprising a disk thatcoordinates movement of the lever arm with the movement of one of saidplurality of individual blister packs into an operative position. 18.The dry powder inhaler of claim 16, further comprising a flow channelconnected at one end to a mouthpiece, the flow channel having an openingthrough which the top of a selected blister pack fits, the blister packbeing held in place against the flow channel by the vibrating element,wherein the piercing element is located on the opposite side of the flowchannel.
 19. The dry powder inhaler of claim 18, further comprising aspring that supports the vibrating element against the selected blisterpack.
 20. The dry powder inhaler of claim 16, wherein the selectedblister pack is dragged by a blister carrier which moves the selectedblister pack in a radial direction.
 21. The dry powder inhaler of claim16, further comprising a flow sensor that senses the breath of the user.22. The dry powder inhaler of claim 21, further comprising a battery anda microprocessor, wherein the microprocessor receives a signal from theflow sensor and controls the activation of the vibrating element.